Tornado Facts

Submitted by ewerner on Mon, 03/21/2011 - 13:18

TORNADO FACTS

Tornadoes have occurred on every continent, except for Antarctica.

About 1,000 tornadoes hit the United States every year.

Most of these touch down in America’s Plain states, an area known as Tornado Alley, which is generally considered to be Oklahoma, Kansas, the Texas Panhandle, Nebraska, eastern South Dakota, and eastern Colorado. Tornadoes, however, can occur almost anywhere in the United States, including west of the Rockies and east of the Appalachians.

Supercell tornadoes are most likely to occur between 3:00 and 9:00 in the evening.

Current tornado warnings have a 13-minute average lead time and a 70% false alarm rate.

Tornadoes have been known to destroy houses, but leave light objects like plates, glasses, lamps, and even paper undisturbed on tables.

They have also been known to pluck the feathers from chickens.

In 1896, a violent tornado drove a piece of wood through the iron Eads Bridge in St. Louis, Missouri.

Tornadoes are known to carry heavy objects, such as cars, up to a distance of a mile, lighter objects, like books and clothing, up to a distance of 20 miles, and really light objects, like paper, up to a distance of 200 miles.

Tornadoes can last from several seconds to more than an hour. The longest-lived tornado in history is really unknown, since so many long-lived tornadoes that were reported before the mid-1900s are now believed to have been a series of tornadoes. Most tornadoes last less than 10 minutes. The longest-lived tornado was likely the Tri-State Tornado, also the country’s deadliest (described below), which may have lasted as long as three and a half hours.

The deadliest tornado in American history was invisible. In 1925, the Tri-State Tornado ravaged a mile-wide path for 220 miles across Missouri, Illinois, and Indiana at 60 to 70 mph—twice the forward speed of the average tornado. It lacked the classic funnel cloud, but the damage was catastrophic: nearly 2,000 people were injured, property losses totaled more than $16 million, and over 700 people died. This event also holds the known record for most tornado fatalities in a single city or town: at least 234 in Murphysboro, Illinois.